The present invention relates to a method and a data processing system for visualizing a comparison result of at least two data structures organized in comparison trees on a graphic display unit. The directory trees stored in at least one memory unit are formed by a like hierarchical arrangement of files and/or folders, which can be compared with one another by means of a microprocessor unit to evaluate structural and/or content differences.
In the field of data processing, files that belong together are frequently stored in so-called folders. To make possible an overview of the allocation of many different folders and associated files, software products offer, for example, so-called file managers.
A file manager typically uses a graphically clear representation of the folders and files within a directory tree. A directory tree, which is a form of organizing a data structure, uses two different status images to display a folder. One status image characterizes the state of an open folder, whereas the second status image represents the folder in its closed state. Once a folder is opened, the folders and/or files contained in it become visible. By opening and closing the folders it is possible to display the branching structure of the directory tree.
The terms file and folder as used hereinafter are synonymous with any objects and object containers of any data processing formats, such as, for example, databases, XML, programming languages, etc. One necessary common feature, however, is that the data structures must be organized in a tree shape.
In practice, a frequently encountered problem is that the contents of at least two directory trees must be compared and the comparison result displayed. The comparison result then shows the differences caused by added or deleted folders and/or files and/or object attributes. Here, the identity of a file or folder is defined by its name and object type. The object attribute of a file or folder is determined by its size, modification time, etc.
Within the context of, for example, an FDA validation or a TÜV acceptance of industrial plants, a comparison of directory trees is used to show the kind of modifications and expansions made in a plant controlled by software. To show programming costs, a comparison of directory trees is typically used to demonstrate the scope of the modifications and expansions. For personal use, a comparison of directory trees may also be used to show differences between the data stored on a desktop computer and a laptop computer.
The software tool “ClearCase” (made by Rational Software Corporation, Version 3.1) is a method for visualizing a comparison result of two data structures organized in comparison trees. After a comparison of the structural or content differences of the directory trees that are to be compared, the comparison result is displayed in two separate windows arranged next to each other in which the differences are marked. The number of windows used for displaying the comparison result corresponds to the number of the directory trees to be compared. Because the differences are marked only at the beginning of a line, the user must cumbersomely move his eyes line by line from left to right to see the comparison result. Thus, the decisive drawback is the lack of a clear arrangement of the comparison result. Furthermore, in the prior art method, the comparison is possible only on a single hierarchical level of the directory tree. A comparison of the entire hierarchical arrangement, including underlying files and/or folders is not possible, and the user must do this manually for each hierarchical level. This requires a significant amount of additional time.